COVID-19 airway protection PPE overview/media/McKinsey/About Us/COVID...specific products or organizations are solely for illustration and do not constitute any endorsement or recommendation

CONFIDENTIAL AND PROPRIETARYAny use of this material without specific permission of McKinsey & Company is strictly prohibited

Update: May 6, 2020

DOCUMENT INTENDED TO PROVIDE INSIGHT BASED ON CURRENTLY AVAILABLE INFORMATION FOR CONSIDERATION AND NOT SPECIFIC ADVICE

COVID-19 airway protection PPE overview

McKinsey & Company 2

Current as of May 4, 2020




COVID-19 is, first and foremost, a humanitarian challenge. Thousands of health professionals are heroically battling the virus, putting their own lives at risk. Governments and industry are working together to understand and address the challenge, support victims and their families and communities, and search for treatments and a vaccine.

Solving the humanitarian challenge is the top priority. Much remains to be done globally to prepare, respond, and recover, from protecting populations at risk to supporting affected patients, families, and communities to developing a vaccine. To address this crisis, responses must be informed by evidence and based on partnership among various stakeholders and sectors, including the medical-product industry and regulatory/compliance agencies.


Current as of May 4, 2020 Current as of May 4, 2020

These materials are preliminary and non-exhaustive and are being made available on a non-exclusive basis solely for information purposes in response to the urgent need for measures to address the COVID-19 crisis.

They reflect general insight and may present potential options for consideration based on currently available information, which is inherently uncertain and subject to change, but do not contain all of the information needed to determine a future course of action.

The insights and concepts included in these materials have not been validated or independently verified. References to specific products or organizations are solely for illustration and do not constitute any endorsement or recommendation.

These materials do not constitute, and should not be interpreted as, policy, accounting, legal, medical, tax or other regulated advice, or a recommendation on any specific course of action. These materials are not a guarantee of results and cannot be relied upon. Future results may differ materially from any statements of expectation, forecasts or projections.

Particularly in light of rapidly evolving conditions, these materials are provided “as is” without any representation or warranty, and all liability is expressly disclaimed for any loss or damage of any kind.

The recipient is solely responsible for all of its decisions, use of these materials, and compliance with applicable laws, rules and regulations. Consider seeking advice of legal and other relevant certified/licensed experts prior to taking any specific steps.

McKinsey & Company 4DOCUMENT INTENDED TO PROVIDE INSIGHT BASED ON CURRENTLY AVAILABLE INFORMATION FOR CONSIDERATION AND NOT SPECIFIC ADVICE


This document is meant to explore select questions around securing a sufficient supply of airway-protection equipment to meet rapidly increasing demand. This document focuses on N95 disposable respirators, surgical masks, and powered air-purifying respirators (PAPRs). Our analysis includes preliminary insights on: intended functionality and critical components product breakdown, requirements, and specifications manufacturing processes and raw materials sourcing strategies and preliminary supplier lists This document should not be used to guide clinical decisions or treatment.

The current environment shows that the supply of airway-protection equipment must be rapidly accelerated to stem shortages already occurring among frontline medical workers



CDC recommends a variety of airway protection options for healthcare professionals, offering a range of protection levels

Source: CDC regulation 42 CFR 84, ASTM F1862, 2101, 2299, https://multimedia.3m.com/mws/media/1794572O/surgical-n95-vs-standard-n95-which-to-consider.pdf, https://www.cardinalhealth.com/content/dam/corp/web/documents/whitepaper/Face%20Mask%20Selection%20Guide.pdf, https://multimedia.3m.com/mws/media/1516101O/3m-vflex-healthcare-particulate-respirator-and-surgical-mask.pdf, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7115281/, https://www.ncbi.nlm.nih.gov/books/NBK294223/, image courtesy of McKinsey design team.

1. ASTM surgical mask standards (Level 1, 2, and 3) are referenced by FDA; not all FDA cleared surgical masks comply with this standard; 2.NIOSH certification mask filtration efficiency for particles ≥ 0.3 μm. Performance results are achieved under testing conditions specified by NIOSH standards, and do not represent filtration efficiency under normal conditions; 3.ASTM standard BFE (Bacteria Filtration Efficiency) for bacterial particles size ≥ 3 μm; PFE(Particle filtration efficiency) for particle size ≥ 0.1 μm. Performance results are achieved under testing conditions chosen by the manufacturer under FDA guidance and do not represent filtration efficiency under normal conditions. Filter tests required by the FDA are much less stringent than NIOSH tests

N95 specification respiratorsReusable Disposable

Nonsurgical respirator Half face

Surgical mask ASTM Level 1 1 Full facepiece

Surgical respirator PAPR

Filtration efficiency ≥95% 2 ≥95% 2 ≥95% 2 BFE ≥95%; PFE ≥95% 3 ≥95% 2 ≥99.97% 2

Fluid protection resistance

N/AN/A>80 mm Hg >80 mm Hg>120 mm Hg>120 mm Hg

Breathability—Differential pressure

<35 mm H20 <35 mm H20 <35 mm H20 <4.0 mm H20 <35 mm H20 N/A, powered air supply

Facial sealing Face sealFace sealFace seal Loose sealFace sealFace seal for tight fitting respiratorsLoose seal for loose-fitting respirators

Designed for fluid protection

NUnknownY YYY

Certification and regulatory body

NIOSH NIOSH NIOSH FDA NIOSH and FDA NIOSH



Disposable N95 respirators




Overview: N95 functions and applicability

Source: https://www.cdc.gov/coronavirus/2019-ncov/hcp/index.html; https://www.cdc.gov/coronavirus/2019-ncov/hcp/respirator-use-faq.html; image courtesy of McKinsey design team

NIOSH certified FDA cleared

N95 respirators

Surgical N95respirators

Surgical masks

Function Reduce small particles inhaled by wearer

Reduce small particles inhaled and expelled by wearer, plus fluid resistance

Protect wearer from splashes and large droplets and minimize particles expelled by wearer

With good fit, protect provider from small particles and have simpler design than surgical N95 P95, R95, N99, P99, R99, P100, R100, P100 are all N95 options that meet higher filtration levels1

With good fit, protect provider from small particles, but not required unless invasive procedure or risk of fluid exposure is present1

Provide HCP with limited protection from exposure due to material type and air leakage due to loose seal to wearer’s face2

COVID-19 applicability

1. https://www.cdc.gov/niosh/npptl/topics/respirators/disp_part/default.html; 2. https://smartairfilters.com/en/blog/coronavirus-pollution-masks-n95-surgical-mask/

CDC guidance requires that nonsurgical N95 respirators provide sufficient protection for HCPs against COVID-19 in most settings.1

CDC states that only HCPs who are working in a sterile field or who may be exposed to high-velocity splashes, sprays, or splatters of blood or body fluids should wear surgical respirators, such as in operative or procedural settings.1

Social enterprise SmartAir notes that surgical masks offer little protection against small particles.2

According to CDC, nonsurgical respirators protect the wearer against hazardous airborne particles, while masks and surgical respirators act as a barrier to fluids.1

McKinsey & Company



8

Product information sheet: Disposable N95 respirators

Not exhaustive

Source: https://www.cdc.gov/coronavirus/2019-ncov/hcp/index.html; https://www.cdc.gov/coronavirus/2019-ncov/hcp/respirator-use-faq.html; image courtesy of McKinsey Design Team.

1. https://www.cdc.gov/niosh/npptl/pdfs/UnderstandingDifference3-508.pdf2. https://www.cdc.gov/coronavirus/2019-ncov/hcp/respirators-strategy/contingency-capacity-strategies.html3. Per WHO technical guidance COVID-19 v4 (11-Mar-2020)

Grade N95:Good breathability with a design that does not collapse against the mouth (eg, duckbill, cup shaped)

Standards: Minimum “N95” respirator according to FDA Class II, under 21 CFR 878.4040, and CDC NIOSH

Technologies required to manufacture: Polypropylene spunbond and meltblown extrusion, heat press and assembly Degree of automation: Fully automated by large players, but for smaller players final assembly may be manual Regulatory and compliance difficulty: Medium Raw-material availability: High-quality polypropylene likely available; intermediate spunbond meltblown spunbond (SMS) nonwoven, especially quality meltblown, in short supply

Raw-material shortages:N95-quality meltblownnonwoven in short supply

FDA Classification:Class II, if surgical3 —may be 510(k) exempt

Usage guidance: Designed for single use1; limited single-wearer reuse considered in contingency scenarios2

Current availability: Very low

Usage

Product description:N95 respirators Product group: Personal protective equipment

Design requirements Manufacturing Product information

McKinsey & Company



9

CDC guidance states that approved respirators under standards similar to NIOSH can be used by HCPs in crisis scenariosPer CDC guidance, respirators graded at N95 level or above in other in other countries are viable options

Country Performance standardAcceptable product classification

Standards/guidance documents

Australia AS/NZS 1716:2012 P3, P2 AS/NZS 1715:2009

Brazil ABNT/NBR 13698:2011 PFF3, PFF2 Fundacentro CDU 614.894

China GB 2626-2006 KN100, KP100, KN95, KP95 GB/T 18664-2002

Europe EN 149-2001 FFP3, FFP2 EN 529:2005

Japan JMHLW-2000 DS/DL3, DS/DL2 JIS T8150:2006

Korea KMOEL-2017-64 Special, 1st KOSHA GUIDE H-82-2015

Mexico NOM-116-2009 N100, P100, R100, N99, P99, R99, P95, R95

NOM-116

US NIOSH 42 CFR 84 N100, P100, R100, N99, P99, R99, P95, R95

OSHA, 29CFR1910.134

Source: https://www.cdc.gov/niosh/npptl/respirators/testing/NonNIOSH.html.



Product breakdown (sample construction): N95 respirators

Source: Derived from expert manufacturing interviews; graphic and technical specifications from an N95 manufacturer; image courtesy of McKinsey design team.

1. Joel Almicar Ramirez, “Evaluation of particle penetration and breathing resistance of N95 filtering face-piece respirators and uncertified dust masks” (PhD thesis, University of Iowa, 2015), https://ir.uiowa.edu/cgi/viewcontent.cgi?article=6337&context=etd

Alternate 2-layer design: Layer 1 (main filter layer):

1.33-mm-thick layer of 5-micron-diameter fibers with 64 g / sq. m density

Layer 2: 0.5-mm-thick layer of 15.5-micron-diameter fibers with 28 g / sq. m density


Filtered air with 95% of >0.3 micron particles removedUnfiltered air

All three layers of SMS can be made in-line or separately in different extruders. All the raw-fabric materials except the filter media should be relatively straightforward to replicate across mills that produce nonwoven synthetic fabric. Filter media is the most technically complex layer in N95 respirators Filter media requires a proprietary recipe to configure the meltblownmachine to create the right performance in the material.

Potential takeaways

Outer cover web—nonsurgical Polypropylene spunbondnonwoven fabric

Provides structure and shape

2.25 mm thick of 22-micron-diameter fibers with 217g/sq. m density

Outer cover web—surgical (ASTM F1862) Impermeable to blood and other fluids

Filter media Polypropylene (PP) meltblown; formulation varies by supplier

3M’s 8510 in 2015, for example, used 1.77 mm thick of 5.5-micron-diameter fibers with 156 g / sq. m density1

Fibers randomly webbed with very low inhomogeneity using corona charge as fibers are extruded; electric charge on fibers attracts particles

Meltblown lacks structural integrity, so quickly layered between two very thin layers of PP spunbond scrim

Pressure drop no more than 35 mm H2O in finished respirator

PP formulation, extrusion die, collector design, configuration, and know-how are proprietary

Inner cover web Polypropylene spunbond nonwoven fabric

0.36 mm thick of 15.5-micron-diameter fibers with 33g/sq. m density



High-level N95 respirator specifications

1. CDC regulation 42 CFR 84; FDA: https://www.fda.gov/medical-devices/personal-protective-equipment-infection-control/n95-respirators-and-surgical-masks-face-masks; 2. Collected through interviews with manufacturing experts; 3. Images courtesy of McKinsey design team; 4. NIOSH Memorandum of Understanding 225-18-006, https://www.fda.gov/about-fda/domestic-mous/mou-225-18-006; testing: https://www.cdc.gov/niosh/npptl/stps/pdfs/TEB-APR-STP-0059-508.pdf; 5.Ramirez, “Evaluation of particle penetration and breathing resistance,” University of Iowa

SpecificationType

Certification and testing4

Testing equipment: Industry standard is TSI 8130ANIOSH approval: N95 masks require a certificate or formal document issued by NIOSH stating that an individual respirator or combination of respirators has met the minimum requirements of 42 CFR Part 84

Examples5

Middle layer N/AMain filter layer: 1.77-mm-thick layer of 5.4-micron-diameter fibers with 156g/m2 density; inhomogeneity assumed to be low to meet N95 spec

Internal layer 0.61-mm-thick layer of 15.5-micro-diameter fibers with 28g/m2 density

Moldex N95 respirator (as measured in 2015, exact model unknown )3M 8510 respirator (as measured in 2015)

0.36-mm-thick layer of 15.4-micron-diameter fibers with 34g/m2 density

External layer 2.27-mm-thick layer of 22-micron-diameter fibers with 217g/m2 density Main filter layer: 1.3-mm-thick layer of 5.1-micron-diameter fibers with 63g/m2

density; inhomogeneity assumed to be low to meet N95 spec

REFERENCES TO INDIVIDUAL PRODUCTS OR COMPANIES ARE SOLELY FOR INFORMATION PURPOSES AND DO NOT CONSTITUTE ANY ENDORSEMENT OR RECOMMENDATION

Source: Head shape image source: CDC: https://www.cdc.gov/niosh/npptl/topics/respirators/headforms/ This image is otherwise available on the CDC website for no charge

Technical2 Thermoformed layered SMS (spunbond-meltblown-spunbond) stack-up of several low-tech layers and one higher-tech layer

Low-tech outer layers: polypropylene spunbond structural inner and outer cover webs

High-tech inner layer: carefully controlled polypropylene meltblown filter media

Functional1 Initial breathing resistance (resistance to airflow) not exceeding 35 mm H20 Initial exhalation resistance not exceeding 25 mm H20

Blocks at least 95% of very small (0.3 micron) test particles

Shape

Typical respirator shapes3 Head shapes

Shaped to conform to face and create good seal on various face sizes and shapes

Head forms for technical specification standards (ISO TC94 Personal Protective Equipment, SC15 Respiratory Protective Devices—National Personal Protective Technology Laboratory of NIOSH)

Duckbill Cup

McKinsey & Company 12McKinsey & Company 12

Overview of constraints in the N95 respirator supply chain

Production process Inventory Likely low nonmed capacity available

Likely some nonmed capacity available

Likely sufficientcapacity available

Dedicated converter

Source: Collected through interviews with experts in the PPE manufacturing industry; image courtesy of McKinsey design team

1. https://www.yicaiglobal.com/news/malion-new-materials-to-invest-usd172-million-on-face-mask-material-plant2. https://www.jqknews.com/news/395294-Sinopec_announced_that_it_would_soon_build_10_melt_blown_cloth_production_lines_with_an_investment_of_about_200_million_yuan.html3. https://www.oerlikon.com/manmade-fibers/en/about-us/news/oerlikon-nonwoven-large-scale-meltblown-sold-to-asia/



Key considerations for supply/ manufacturing

End-to-end producers taking raw polypropylene to finished mask exist but are likely at max capacity.

Splitting production of SMS nonwoven from mask conversion is possible but converters should ideally be near SMS producer to minimize shipping delay and cost.

Material and equipment requirements

Manufacturing process

Polypropylene formulation: Need formulation/blend from IP owners

High-grade polypropylene, ideally without pigment or TiO2

Meltblown: Exxon Achieve Advanced PP6936G2

Spunbond: Exxon Vistamaxx 70020BF

Reifenhauser Reicofil is the most common machine and it uses dies from Hills Inc. in Melbourne, Florida, to make N95-quality SMS. It has production capacity up to 1.8 million respirators per day

Oerlikon SMS machines are a potential alternative3

Biax Fiberfilm, a Wisconsin company, also makes a form of meltblown equipment capable of N95-quality SMS

Reicofil has shortened lead time of 3–5 months for new capacity in existing factory

Significant capital and configuration cost investment per line1 2

Special extrusion die (<5um EDM holes): Need backup die from current manufacturers

Bonding pattern used in thermoforming and die-cutting critical as wrong settings may destroy uniform porosity

Patented patterns available (contain temperature, pressure, line speed)

Experienced filtration engineers to configure machinery

Extrude spunbondnonwoven outer/inner

Extrude meltblownnonwoven filter

Fabric mills

Nonwoven SMS fabric (spunbond-meltblown-spunbond sandwich)

Raw materials

Attach straps and nose piece, package

Thermoform and die-cut

Mask-converting machinery Blank

respirators Finished packaged respirators

McKinsey & Company



13

Meltblown is manufactured in multiple facilities within the US for a variety of end products

Company State(s)3M CT, NE, TN, MN, WIAtex GABrady SPC KYFiber Dynamics NCHollingsworth & Vose VAHDK Industries TNJohns Manville MSKimberly-Clark AR, MSLydall Performance Materials NHMeltBlown Technologies GAMonadnock Non-Wovens PANPS Nonwovens WISpilltech MDSWM International DE

Current capacity

Usage

Total production capacity of meltblown material in North America is estimated to be around 175,000 metric tons in 2018,2 but unclear how much of this capacity can be configured to meet N95 requirements

Filtration media for HVAC and water, wipes, absorbent hygiene, vehicle construction for NVH1, sorbents, medical/surgical products, and apparel

1. NVH = noise, vibration, harshness; 2. Derived from industry consortium experts

Examples of companies with melt blown production capacity that can potentially produce N95 filter media

Source: Image courtesy of McKinsey Design Team REFERENCES TO INDIVIDUAL PRODUCTS OR COMPANIES ARE SOLELY FOR INFORMATION PURPOSES AND DO NOT CONSTITUTE ANY ENDORSEMENT OR RECOMMENDATION

Not exhaustive

McKinsey & Company



14

Meltblown production lines are available from multiple suppliers

1. https://www.reicofil.com/system/uploads/attachment/file/58f8ab2f59d9e623a9d48e54/REI-RF5-Boschuere-Low.pdf2. Calculated based on 24 hr/day, 365 days/year operation at 270 kg/hr/m with maximum roll width, maximum output from specification above3. Calculated based on 24 hr/day, 365 days/year operation at 70 kg/hr/m with maximum roll width, maximum output from specification above4. https://www.oerlikon.com/manmade-fibers/en/about-us/news/oerlikon-neumag-at-cinte-2010-all-in-one-in-nonwoven-production-equipment/5. Calculated based on 24 hr/day, 365 days/year operations at 1500 kg/h, unspecified width, per https://fiberjournal.com/geo-synthetics-significance-and-application-in-everyday-life/6. https://www.oerlikon.com/manmade-fibers/en/about-us/news/oerlikon-nonwoven-large-scale-meltblown-sold-to-asia/, it is unclear what assumptions of production run time per day and per year are used in this calculationsImage courtesy of McKinsey design team.


Example suppliers

Example suppliers Select characteristics

Oerlikon Neumagnonwoven systems

Estimated nominal spunbond output up to 13.1 ktons/year5

Nominal meltblown output up to 1.2 ktons/year6

Up to 7000mm4

Standard line width

Reifenhauser REICOFIL Production rate up to 1200 m/min1

Estimated nominal spunbond output up to 12.3 ktons/year2

Estimated nominal meltblown output up to 3.2 ktons/year3

Up to 5200mm1

McKinsey & Company



15

Converting machinery, ranging from automated single line to multistep lines, is available from different suppliers Example assembly-line types and suppliers


1. http://www.ycnicety.com/show/154.html, https://www.lihanmachine.com/zhediekouzhaoshebei/1067.html2. https://cn.made-in-china.com/gongying/kuaiyudacom-cXWxDBYMnnVF.html | 3. https://cn.made-in-china.com/gongying/kuaiyudacom-EKcQhyUJRxkm.html4. https://cn.made-in-china.com/gongying/kuaiyudacom-hBWmbXpKbxkY.html5. https://www.ncm-machinery.com/mask-machine/ | 6. http://fdinonwovens.com/index.php/about_us | 7. http://www.trm-machinery.com/?lang=en | 8. https://www.elmarco.com/Image courtesy of McKinsey design team.

Other NCM Nonwoven Converting Machinery Co., Ltd.5

TRM-Top Rank Machinery Inc.7

Fiber Dynamics, Inc.6

Elmarco8, a nanofiber machine maker

After-process production line4

18-22 Can integrate multiple steps (eg, labels, assembly, packing)

KYD 330,000

Welding and cutting machine3

15 KYD 65,000

Cup-Shaped N95 Machinery

50-60 KYD Cover-making machine2

65,000

Folded-N95 Assembly Line

Automated folded mask line

25-55 KYD (used by Honeywell) Yicheng Lihan1

400,000-500,000

Throughput (pcs/min) Type Supplier example Price (RMB)

McKinsey & Company 16McKinsey & Company 16

Representative testing process and key standards

Not exhaustive

1 https://www.cdc.gov/coronavirus/2019-ncov/hcp/respirators-strategy/crisis-alternate-strategies.html2. Derived from manufacturing-expert interviews and researchImage courtesy of McKinsey design team

Test-equipment manufacturers (select examples)2

TSI: Automated-filter tester (eg, TSI 8130A), most commonly used by manufacturers Air Techniques International: Protective Mask Leakage Tester (PMLT) for full design testing of masks or 100X Automated Filter Tester

Test standards Filtration-efficiency standard is established by multiple regulatory agencies: US NIOSH-42CFR84; Europe EN 149-2001; China GB2626-2006; Japan JMHLW-2000 JIS T8150: 2006; and others as equivalent per CDC guidance1

Other testing, such as bacterial-filtration efficiency, pressure drop, and microbial limit, can be considerations for regulatory approvalsIn-line testing for mask design can be carried out by optical inspection systems



Tests for raw material

Representative testing approach Raw-material

testingSteps to ensure quality of nonwoven fabric inputs

Sample testing before shipment

Tests for QA/QC of finished goods

In-line inspectionAutomated optical or manual inspection before packaging

Sample test in laboratory

Manufacturers should ensure that test standards are appropriate for end-use markets and adhere to all legal and regulatory requirements.



The COVID-19 response team has developed knowledge around five categories of medical supply interventions

NON EXHAUSTIVE

Maximize capacity of existing manufacturers3

Develop alternate specifications and designs(to enable one or more of the above supply interventions)

5

Redeploy existing inventory from other industries2

Maximize usage of available supply1

Unlock new capacity for manufacturing4




Multiple options can help increase the supply of N95 respirators in the short and medium term

1. https://www.fda.gov/media/136403/download; https://www.fda.gov/media/136664/download; https://www.fda.gov/media/136663/download REFERENCES TO INDIVIDUAL PRODUCTS OR COMPANIES ARE SOLELY FOR INFORMATION PURPOSES AND DO NOT CONSTITUTE ANY ENDORSEMENT OR RECOMMENDATION

2 41 5

Can existing inventory be gathered from nonessential users of medical N95 respirators, or can distributors of nonmedical N95 respirators collaborate to maximize use of existing inventory?

Can strategies to reuse and extend the life of N95 respirators be developed (e.g., using hydrogen peroxide, UV irradiation)?

Can alternate specs and designs be developed using current or alternate material that meets performance and regulatory requirements? Can products now approved by the FDA1 be sourced from countries with similar standards and specifications (e.g., FFP2 from EU and selected manufacturers of KN95 from China)?

Is it possible to identify additional capacity to manufacture N95 or subcomponents within contract manufacturers and other adjacent industries (e.g., textiles and diaper manufacturers)?

Maximize usage of available supply

Redeploy existing inventory from other industries

Develop alternate specifications and design

Unlock new capacity for manufacturing

Potential approaches that go beyond traditional sources of supply




1. https://inside.battelle.org/blog-details/covid-19-deploying-a-critical-new-ppe-decontamination-system; https://techcrunch.com/2020/03/30/fda-grants-emergency-authorization-to-system-that-decontaminates-n95-respirator-masks-for-re-use/


1a

FDA granted authorization to Battelle’s system, which disinfects N95 respirators with concentrated hydrogen peroxide

Battelle (a research, development, and lab-management company) has received special emergency authorization to use its Critical Care Decontamination System (CCDS) to reprocess used N95 respirator masks with concentrated hydrogen peroxide1

Conclusions below were developed by the authors cited on this slide

System enables single-use respirators to be used up to 20 times, with a 2.5-hour decontamination process between uses

System is already in operation at Battelle’s Ohio facility, which has a capacity of up to 80,000 masks per day; facility is working with Columbus-based OhioHealth and will soon work with three other major healthcare systems

Disinfected N95 masks will go back to the same healthcare facility they came from, labeled with a serial number that provides tracking and collects information on reuse



NIOSH/CDC research concluded that UVGI could be used to effectively disinfect disposable respirators for reuse1. National Center for Biotechnology Information,

https://www.ncbi.nlm.nih.gov/pubmed/258064112. Nebraska Medicine, N95 Filtering Facepiece

Respirator Ultraviolet Germicidal Irradiation (UVGI) Process for Decontamination and Reuse, https://www.nebraskamed.com/sites/default/files/documents/covid-19/n-95-decon-process.pdf DOCUMENT INTENDED TO PROVIDE INSIGHT BASED ON CURRENTLY AVAILABLE INFORMATION FOR CONSIDERATION AND NOT SPECIFIC ADVICE

1b Conclusions below were developed by the authors cited on this slide

Research by NIOSH/CDC concluded that ultraviolet germicidal irradiation (UVGI) could be used to effectively disinfect disposable respirators for reuse1

UVGI exposure led to a small increase in particle penetration (up to 1.25%) and had little effect on flow resistance

UVGI exposure had a more pronounced effect on strength of respirator materials. At higher UVGI doses, strength of layers of respirator material was substantially reduced (in some cases, by >90%)

Changes in strength of respirator materials varied considerably among different models of respirators

Maximum number of disinfection cycles will be limited by respirator model and UVGI dose required to inactivate pathogen

Nebraska Medicine has developed a decontamination procedure involving UVGI2 Decontamination room has two UVGI towers on either

side, each of them equipped with eight 254-nm bulbs; walls and ceiling were covered with UV-4 reflective coating prior to initiating decontamination program

Delivered UVGI exposure dose is monitored with a room UVGI meter that can be initiated and monitored from outside room to prevent damage to eyes and skin

Respirators are secured on wires strung across room during process

Plan is to decontaminate and reuse N95 FFRs multiple times until respirator fit is affected



2. Options to consider for redeploying N95 respirators

1. https://www.fda.gov/medical-devices/personal-protective-equipment-infection-control/n95-respirators-and-surgical-masks-face-masks


MRO distributors have expressed willingness to collaborate with an established coordinating body on this effort.

Can all nonessential purchases of N95 respirators be stopped and existing inventory returned to MRO distributors?

Can all nonessential use in industries currently using N95 respirators be stopped until shortage is resolved?

Can nonmedical N95 respirators be used when next best alternative is operating without respirators?1

McKinsey & Company



22

3. Potential ways to unlock new capacity for manufacturing

Source: Collected through interviews with experts in the PPE manufacturing industry.

Levers Description Examples

Repurpose similar machinery

Manufacturing: Up-configure existing machinery used for non-N95 applications

Meltblown process: Some alternate extruders can be modified with the right extrusion die, which can be potentially supplied by diemakers or others with spare dies Conversion process: Textile industry has similar production lines that can be modified

Arrange financing options for manufacturers

Due to high upfront capital requirements for production lines, financing options may be needed for meltblown producers to up-configure or retool to produce meltblown fabric

Enable loans or grants for meltblown machinery capex and configuration expense

Product testing: Leverage qualified testing equipment with similar capabilities to add testing capacity

Some research institutions (eg, NC State Nonwovens Institute) may have testing equipment Key suppliers of testing equipment are likely to know availability and location of existing testing equipment in adjacent industries (e.g., air-filter suppliers for HVAC or automotive cabins)



5. FDA approves of some products with similar standards, with some supplier restrictions3,4,5Comparison of filtering facepiece respirators with different performance standards1

Country or region US Europe China Australia Korea Japan

Certification/class (standard)

N95 (NIOSH-42C FR84)

FFP2 (EN 149-2001)

KN95 (GB2626-20 06)

P2 (AS/NZ 1716:2012)

1st Class (KMOEL -2017-64)

DS (JMHLW-Notification 214, 2018)

Filter performance(must be ≥ X% efficient)

≥ 95% ≥ 94% ≥ 95% ≥ 94% ≥ 94% ≥ 95%

Flow rate 85 L/min 95 L/min 85 L/min 95 L/min 95 L/min 85 L/min

Total inward leakage (TIL)* – tested on human subjects performing exercises

N/A ≤ 8% leakage (arithmetic mean)

≤ 8% leakage (arithmetic mean)

≤ 8% leakage (individual and arithmetic mean)

≤ 8% leakage (arithmetic mean)

Inward leakage measured and included in user Instructions

Inhalation resistance – max pressure drop

≤ 343 Pa ≤ 70 Pa (at 30 L/min) ≤ 240 Pa (at 95 L/min) ≤ 500 Pa (clogging)

≤ 350 Pa ≤ 70 Pa (at 30 L/min) ≤ 240 Pa (at 95 L/min)

≤ 70 Pa (at 30 L/min) ≤ 240 Pa (at 95 L/min)

≤ 70 Pa (w/valve) ≤ 50 Pa (no valve)


FDA’s EUAs from March 28, 2020, April 3, 2020, and May 7, 2020 allow respirators from EU, Australia, Korea, and Japan3,5

but only select suppliers from China (see latest CDC guidance and FDA EUAs on PPE2,3,4,5)

While the listed product classifications have similar performance requirements to NIOSH-approved devices, CDC claims no knowledge about sustained manufacturer quality system and product quality control for these products2

Point of use assessments are being conducted by NIOSH to verify quality and filter efficiency, and to align EUAs2

1. https://multimedia.3m.com/mws/media/1791500O/comparison-ffp2-kn95-n95-filtering-facepiece-respirator-classes-tb.pdf2. https://www.cdc.gov/niosh/npptl/respirators/testing/NonNIOSH.html 3. https://www.fda.gov/media/136403/download; https://www.fda.gov/media/136664/download4. https://www.fda.gov/media/136663/download5. https://www.fda.gov/medical-devices/emergency-situations-medical-devices/emergency-use-authorizations#covid19ppe



Surgical masks






According to the CDC, surgical masks are less effective in filtering small particles and protecting the wearer than N95 respirators

Source: https://www.cdc.gov/coronavirus/2019-ncov/hcp/index.html; https://www.cdc.gov/coronavirus/2019-ncov/hcp/respirator-use-faq.html Image courtesy of McKinsey design team

1. https://www.cdc.gov/niosh/npptl/topics/respirators/disp_part/default.html1. https://smartairfilters.com/en/blog/coronavirus-pollution-masks-n95-surgical-mask/

Surgical masks are designedto protect wearer from splashes and large droplets and minimize particles expelled by wearer. Face masks fit loosely and do not prevent leakage around mask edge when user inhales.

Certification NIOSH certified FDA class II guidelines

Function Filter out small particles inhaled by wearer

Protect wearer from splashes and large droplets and minimize particles expelled by wearer

COVID-19 applicability

With good fit, protect provider from small particles; have a simpler design than surgical N95

Provide limited protection to HCP due to facial seal leakage1

Design Test fitted to seal tightly around wearer’s nose and mouth

Typically rectangular shapedand loop over wearer’s ears

N95 respirators Surgical masks


McKinsey & Company



26

Product information sheet: Surgical masks

1. https://www.cdc.gov/niosh/npptl/pdfs/UnderstandingDifference3-508.pdf; 2.ASTM levels determined by ASTM F2100-11 standards, ASTM F1862, ASTM F2299; not all surgical masks comply to ASTM standards; 3. https://www.fda.gov/regulatory-information/search-fda-guidance-documents/surgical-masks-premarket-notification-510k-submissions

Source: https://www.cdc.gov/coronavirus/2019-ncov/hcp/index.html; https://www.cdc.gov/coronavirus/2019-ncov/hcp/respirator-use-faq.html; https://www.fda.gov/files/medical%20devices/published/Guidance-for-Industry-and-FDA-Staff--Surgical-Masks---Premarket-Notification-[510(k)]-Submissions--Guidance-for-Industry-and-FDA-(PDF-Version).pdf; https://www.halyardhealth.co.uk/media/16340001/hc352_00-uk_facethefacts_astm_2014.pdf, image courtesy of McKinsey design team.

ASTM surgical mask performance standards2

Product information Product description:Surgical masks3; may be labeled as surgical, isolation, dental, or medical procedure masks

Product group: Personal protective equipment

Product function:A loose-fitting, disposable device that helps protect wearer from large-particle droplets, splashes, sprays, or splatter that may contain germs; may also help protect others from exposure to wear’s saliva and respiratory secretions1

Regulations:Surgical masks are regulated under 21 CFR 878.4040. FDA Class II3

Technologies required to manufacture:Polypropylene, usually in SMS form (spunbond-meltblown-spunbond)

Level 1 Level 2 Level 3 Description

>80 mmHg >120 mmHg >160 mmHg Resistance to penetration by synthetic blood

Fluid protection resistance

<4.0 <5.0 <5.0 Breathing pressure difference across the mask

Differential pressure test

≥95% ≥98% ≥98% Ability of mask to prevent passage of aerosolized bacteria

BFE (bacteria-filtration efficiency standard – 3 μm)

≥95% ≥98% ≥98% Filtration test using unnaturalized 0.1-micron polystyrene latex spheres

PFE (particle-filtration efficiency standard – 0.1 μm)

Class 1 Class 1 Class 1

Regulations and technology

Resistance to penetration by synthetic blood

Flammability

Not exhaustive



According to the FDA, surgical masks do not provide as good facial seal as N95

Source: https://www.crosstexbms.com/media/1097/maskenomics-crosstexctx1216_p.pdf, https://smartairfilters.com/en/blog/comparison-mask-standards-rating-effectiveness/, https://www.fda.gov/medical-devices/personal-protective-equipment-infection-control/n95-respirators-and-surgical-masks-face-masks, https://www.halyardhealth.co.uk/media/16340001/hc352_00-uk_facethefacts_astm_2014.pdf, https://blogs.cdc.gov/niosh-science-blog/2009/10/14/n95/, image courtesy of McKinsey design team.

FDA states that surgical masks do not provide complete protection from germs and other contaminants because of the loose fit between the mask and the face1

NIOSH certification mask filtration efficiency for particles ≥ 0.3 μm. Performance results are achieved under testing conditions specified by NIOSH standards, and do not represent filtration efficiency under normal conditions

ASTM standard BFE (Bacteria Filtration Efficiency) for bacterial particles size ≥ 3 μm; PFE (Particle filtration efficiency) for particle size ≥ 0.1 μm. Performance results are achieved under testing conditions chosen by the manufacturer under FDA guidance and do not represent filtration efficiency under normal conditions. Filter tests required by the FDA are much less stringent than NIOSH tests2

1.https://www.fda.gov/medical-devices/personal-protective-equipment-infection-control/n95-respirators-and-surgical-masks-face-masks#s4

2.https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7115281/

BFE: ≥98%

PFE: ≥98%

BFE: ≥95%

PFE: ≥95%

BFE: ≥98%

PFE: ≥98%

0.3 Microns: ≥80% 0.3 Microns: ≥94% 0.3 Microns: ≥99%

Filtration Effectiveness Mask type Facial seal Standards Single-use face mask Loose seal BFE: ≥95%

PFE: NA

China: YY/T0969

BFE: ≥95%

PFE: ≥95%

BFE: ≥98%

PFE: ≥98%

BFE: ≥98%

PFE: ≥98%

Surgical mask Loose seal BFE: ≥95%

PFE: ≥30%

China: YY 0469

Loose seal Level 1 Level 2 Level 3 USA: ASTM F2100

Loose seal Type 1 Type 2 Type 3 Europe: EN 14683

Good face seal FFP1 FFP2 FFP3 Europe: EN 149:2001

N95 respirator Good face seal N95/KN 95 N99/KN 99 N100/KN 100 USA: NIOSH (42 CFR 84)

0.3 Microns: ≥95% 0.3 Microns: ≥99% 0.3 Microns: ≥99.97%

China: GB2626



Current as of May 4, 2020JHI1 research shows that integral visors help consistently reduce particles/influenza virus inside surgical masks

1. Journal of Hospital Infection; 2. Influenza plaque reduction factor = Influenza virus titre of external air sample / Influenza virus of internal air sample; 3. (Particle) reduction factor = Particle concentration outside the mask/Particle concentration inside the mask; 4. https://www.fda.gov/medical-devices/personal-protective-equipment-infection-control/n95-respirators-and-surgical-masks-face-masks#s4

Surgical masks, while imperfect in completely negating the introduction of aerosol influenza particles, still do reduce the amount of particles entering into the respiratory system depending on the design of the face mask

Mask type Double-strap tie surgical mask with integral splash visor

Typical double-strap tie surgical mask

The design of the surgical masks matter Surgical masks also do not provide complete protection because of the loose fit4. Therefore any design changes, e.g., adding a visor or metal adjuster at the nose or at the chin that could contribute to a better facial seal, can potentially increase the overall protection level

Influenza plaque reduction factor2

(Particle) reduction factor3

10

1

100

Surgical masks

Source: Booth, C. Makison. “Effectiveness of Surgical Masks against Influenza Bioaerosols.” Journal of Hospital Infection, vol. 84, 31 May 2013, pp. 22–26. https://www.sciencedirect.com/science/article/abs/pii/S0195670113000698; image courtesy of McKinsey design team

McKinsey & Company



29

Studies find that while surgical masks are not as effective as N95 respirators, they block out some aerosol particles

Source: https://smartairfilters.com/en/blog/coronavirus-pollution-masks-n95-surgical-mask/

99.7% 99.6% 99.4% 99.1% 98.7% 97.5% 95.2% 92.9% 92.3%86.5% 85.3% 84.4%

79.6%

63.0%56.5%

3M 9501

3M 9211

3M 9010

LvDun 3M 9332

Vog-mask

3M 9332

3M 9001V

3M 9003

3M 9001V

I can Breathe

Toto-bobo

Respro 3M 9001V

Surgical mask

N95 respirator Surgical mask There are studiesthat demonstrate a certain degree of efficacy of surgical masks despite the facial-seal factors. While not performing at the level of N95 respirators—empirically shown to block >97% of the 0.01 μmparticles (10 times smaller than coronavirus particles)—surgical masks show 63% block rate fortiny virus-sized particles despite facial leakages.

Particles blocked during fit test for different mask variantsParticles .01 – 1 Microns blocked, %

McKinsey & Company



30

According to the JHI,1 wearing multiple masks may help reduce small-particle penetration, but not as well as an N95

Source: C. Makison Booth, “Protecting healthcare staff from severe acute respiratory syndrome: Filtration capacity of multiple surgical masks,” Journal of Hospital Infection, no. 59 (2005), 365–68, https://www.sciencedirect.com/science/article/abs/pii/S0195670113000698; image courtesy of McKinsey design team.

1. Journal of Hospital Infection

Increasing pressure difference and

decreasing breathability<5mm H20 <35 mm H20Breathability

1 2 3 5 1Number of masks worn

63% 78%74% 82% 95%Particle reduction (measuring 0.02-1 μm)

Surgical Surgical Surgical Surgical N95Type

Research has shown that use of up to five surgical masks overlapping one another further reduces particle penetration to wearer, but not to the level of an N95

Breathing comfort (measured in differential pressure) is unknown for multiple masks but likely reaches uncomfortable levels

Journal of Hospital Infection shows that aerosol penetration through a surgical mask is highly dependent on particle size, mask construction, and breathing flow rate

In this study, volunteers wearingmasks simulated various activities of HCPs, including breathing, deep breathing, turning head from side to side, flexing and extending head, talking loudly, and bending over followed by normal breathing again



Surgical masks are designed with rapid mass manufacturing in mind

Source: Collected through interviews with experts in the PPE-manufacturing industry; image courtesy of McKinsey design team

Water repellant

Breathable

Inner layer

Outer layer

Center layer

1 customized machine cuts and bonds 3 layers in 1 process 5 components of surgical masks

Metal nose bands and elastic ear loops are placed and ultrasonic bonded4 5 Metal nose band Elastic ear loops

2 structural components

3

2 Center layer Material: Polypropylene SMS nonwoven fabric

Function: Filter particles and bacteria according to ASTM standards

1 Inner layer Material: Spunbonded nonwoven fabric (same material as exterior of disposable ice bag)

Function: Enhance wearer's comfort

Outer layer Material: Spunbonded nonwoven fabric

Function: Less soft than inner layer, holds desired color, and is coated for fluid resistance

3 protective layers 3 fabrics are fed into machine from rollersMaterial feed

Edges of mask are bonded using ultrasonic bonding machines or adhesives (ultrasonic provides stronger and more hygienic seal)

Edge bonding

Masks are stamped in desired shapeDie-cut

Fabrics are laid in desired accordion structureLayering

Component bonding




Surgical masks are simpler to manufacture than N95 respirators due to smaller bonding surfaces and lack of shape molding

Source: Collected through interviews with experts in the PPE-manufacturing industry.


Customized single machine

Layering Edge bondingMaterial feed Die-cut WIP inventory

Raw material inventory

Both processed in equivalent clean-room environment

Component bonding

Surgical mask manufacturing process

Fabrics are laid in desired accordion structure

3 fabrics are fed into machine from rollers

Edges of masks are bonded using ultrasonic bonding machines or adhesives (ultrasonic provides stronger and more hygienic seal); adhesives were commonly used 5+ years ago

Masks are stamped in desired shape

Metal nose bands and elastic ear loops are placed and ultrasonic bonded

Similar materials, but nonwoven layers on respirators need to be denser than surgical masks

Ultrasonic bonding on respirators needs to be done throughout surface instead of just edges

Mask needs to be pressed and thermoformed into coconut shape before being die-cut

Differences from respirator manufacturing process


Current as of May 4, 2020Industry experts suggest several adjacent industries may have capabilities to mold, bond, and die-cut similar fabrics

Source: Collected through interviews with experts in the PPE-manufacturing industry.



Potential nonincumbent manufacturers Things to consider

The final conversion stage of respirators and masks is currently set up in clean-room environments by incumbents to guarantee the hygienic state of the products. Given that raw materials are to be made in non-clean-room production lines, could nonincumbents convert in gray space but add sterilization to ensure a hygienic product? Though there are flat-folded respirators on the market, HCPs are more accustomed to coconut shapes, and all fit tests and training are conducted around coconut-shape respirators. Suddenly changing the shape could require change management. Nonincumbent manufacturers would require regulatory review and approval to produce certified masks and respirators.

Surgical mask N95 production

Reasoning Expertise in 3-layer-edge ultrasonic bonding Materials used are similar nonwovens

Expertise in surface-ultrasonic-molding 3 layers onto a cup shape—may just need to change the mold Retail volumes are down—many factories currently running at low capacity

Industry Manufacturers of feminine-care and baby products: hygiene pads, diapers, underpads, puppy pads

Bra manufacturers for typical coconut-shaped respirators Manufacturers of feminine-care and baby products for flat-fold respirators

Types



PAPR(powered air-purifying respirator)


McKinsey & Company



35

OSHA allows the use of PAPR1 during aerosol-generating procedures and when N95 respirators are not available2

Source: https://www.osha.gov/pls/oshaweb/owadisp.show_document?p_id=12716&p_table=standardsImage courtesy of McKinsey design team

1. Powered air-purifying respirator | 2. https://www.osha.gov/Publications/OSHA3990.pdf | 3. Assigned protection factor, a term used by OSHA to determine how well a respirator/filter combination will protect an individual from external contaminants; an APF of 25 means that no more than one 25th of the contaminants to which the worker is exposed will leak into the inside of the mask, https://affygility.com/potent-compound-corner/2017/10/19/the-proper-use-of-assigned-protection-factors-and-maximum-use-concentrations.html | 4. APF of 25 without additional testing | 5. https://www.cdc.gov/coronavirus/2019-ncov/hcp/respirators-strategy/index.html | 6. https://www.ncbi.nlm.nih.gov/books/NBK294223

Most commonly used type

Tight fitting Full facepieceHalf mask Hood Helmet

Key metrics Respiratory protection (APF)3 1000 50 254 254

Min airflow rate 115 liters/min 115 liters/min 170 liters/min 170 liters/min

Loose fitting

COVID-19 applicability OSHA recommendations2

When disposable N95 filtering facepiece respirators are not available, consider using PAPR with high-efficiency particulate-absorbing (HEPA) filter For any operations or procedures likely to generate aerosols, consider using PAPRs, as they are more protective than filtering facepiece respirators PAPRs should not be used in surgical settings due to concerns that the blower exhaust and exhaled air may contaminate the sterile field5

PAPRs protect the user by filtering out contaminants in the air and use a battery-operated blower to provide the user with clean air.6

Use of tight-fitting PAPRs requires fit testing; use of loose-fitting PAPRs does not require fit testing.6

McKinsey & Company



36

Functions and user experience differ greatly between PAPRsand disposable N95 respirators

Not exhaustive

1. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4589166/ ; 2. https://www.cdc.gov/niosh/npptl/topics/respirators/disp_part/respsource3end.html3. https://www.ncbi.nlm.nih.gov/books/NBK294223; 4. Derived from healthcare expert interviews and research; 5. https://blogs.cdc.gov/niosh-science-blog/2017/11/02/noshave/ 6. https://www.ncbi.nlm.nih.gov/books/NBK294223/Image courtesy of McKinsey design team

Not required for loose-fitting piece3 Required, has restriction on facial hair5Fit test

Purifies the ambient air and feeds into the respirator; discharged air is not filtered3 Filters both inhaled and exhaled airFiltration

Loose parts such as hoses, cords, and filters can get dislodged in congested emergency environments3

One-piece design that does not easily become loose compared to PAPR

Vulnerability to external environment

Equipment might get in the way of different working postures and have difficulty remaining in place to provide uninterrupted protection3

One-piece design that does not easily become loose compared to PAPR

Stability of level of protection

Must be cleaned and disinfected according to manufacturer’s reprocessing instructions prior to reuse4 Discard after single use; special operational system needed for approved decontamination process

Ease of disinfection between patients

Additional training might be required when using a new type4 Easier to learn and train than PAPRTraining

PAPR(Most common hood and helmet systems, >$1,000)

Disposable N95 respirator (<$10)

Function ≥25 101Assigned protection factor

Yes for full-facepiece PAPRs and some loose-fitting PAPRs6 NoFluid protection for eye

Hard to repair when damaged, need assistance from manufacturer with high cost4 Can be discarded and replaced at low costMaintenance

User experience Purified air is supplied into hood/helmet by blower Differential pressure <35 mmH20Breathability

Some models might have restrictions on neck movement, ability to hear each other4 Less restriction on movements than PAPRRestriction on movements

Reusable; filter change needs to follow manufacturer’s recommendation or when damaged, soiled, or causing noticeable increase in breathing resistance2

Follow manufacturer’s recommendation or discard whenever they are damaged, soiled, or causing noticeable increase in breathing resistance2

Reusability



Several regulatory bodies overseegovernance of PAPR

1. https://www.cdc.gov/coronavirus/2019-ncov/hcp/infection-control-recommendations.html2. https://www.cdc.gov/niosh/docs/2018-166/pdfs/2018-166.pdf?id=10.26616/NIOSHPUB20181663. https://www.ncbi.nlm.nih.gov/books/NBK294223/4. “Use of alternatives to N95 respirators,” https://www.cdc.gov/coronavirus/2019-ncov/hcp/respirators-strategy/index.html5. https://www.3m.com/3M/en_US/safety-centers-of-expertise-us/respiratory-protection/respirator-selection/6. https://www.cdc.gov/niosh/npptl/topics/respirators/cel/DOCUMENT INTENDED TO PROVIDE INSIGHT BASED ON CURRENTLY AVAILABLE INFORMATION FOR CONSIDERATION AND NOT SPECIFIC ADVICE

Per CDC recommendations, PAPRs4 could be considered as alternatives to N95 respirators and surgical masks in nonsurgical settings as long as they are compliant with OSHA regulations. In US, PAPR filters are required to be HEPA rated, and need to provide at least 99.97% filtration.5

PAPR models approved by CDC for medical use are listed in NIOSH Certified Equipment List (CEL) database.6

Respiratory-equipment certification

42 CFR 84 NIOSH Respiratory-protection devices

DIN EN 12942 EN

Respiratory-protection PPE

1910.1342 OSHA Filtering devicesSC153 ISO

Respiratory-protection devices

TC943 ISO

General US certificationsfor PAPRs used in medical setting1

per CDC General international standardsfor PAPR per NIH summary3

DescriptionStandard Body DescriptionStandard Body

McKinsey & Company



38

Product information sheet: Powered air-purifying respirator

Not exhaustive

Source: Derived from interviews with supply-chain experts; image courtesy of McKinsey design team.

1. https://www.cdc.gov/coronavirus/2019-ncov/hcp/infection-control-recommendations.html, https://www.ncbi.nlm.nih.gov/books/NBK294223/2. Derived from interviews with supply-chain experts

Standards: 42 CFR 84 (NIOSH) and 1910.134 (OSHA) in US DIN EN 12942 (EN), SC15 (ISO), TC94 (ISO) in international standards for PAPR per NIH summary1

Usage Usage guidance: Designed to be reusable and provide protection when equipped with the appropriate cartridge, canister, or filter Current availability: Low2

Product information Manufacturing Design requirements Product description:Powered PAPR; eg, 3MTM

VersafloTM

Product group: Personal protective equipment

Technologies required to manufacture: Extruded tube, battery-powered blower, and facepiece assembly (head top, hood, or helmets) Degree of automation: Subassemblies are highly automated while final assemblies may require manual work Regulatory & compliance difficulty: Medium Raw-material availability: Low, especially blower, which is made from DC motor and fan module, battery, and airtight container; airtight container is the bottleneck of expanding blower production because expanding airtight container production needs >1 month lead time to produce additional sets of tooling

Lightweight battery blower for mobility and durability to provide filtered air to a convenient and safe head top



Product breakdown (example construction): Powered air-purifying respirator PAPR is a set of three subassemblies: Head top, tube, and blower

A battery-powered blower that, in the plastics enclosure, has a motored fan pulling air through HEPA, which filters at least 99.97% efficiently for removing particles ≥0.3 μm1

A tightly ventilated tube that is made from thermally extruded resin materials (HDPE4) or rubber3; it directs filtered air from the blower to the head top

A head-top unit that, depending on environment needs, can be a half mask, full facepiece, helmet/hood, or loose-fitting piece; its design varies and can be disposable or reusable (the latter requires maintenance and sanitization)5

1. CDC Environmental Infection Control Guidelines - Air: https://www.cdc.gov/infectioncontrol/guidelines/environmental/appendix/air.html2. CDC and NIOSH: https://www.cdc.gov/niosh/docs/99-143/pdfs/99-143.pdf3. https://safety.honeywell.com/content/dam/his-sandbox/products/respiratory-protection/documents/HS_primair_100_series_hoods_810.pdf4. High-density polyethylene5. https://ohsonline.com/Articles/2019/05/01/Why-Pick-a-PAPR.aspx?Page=3

Not exhaustive

Powered air-purifying respirators can be reusable but must be carefully maintained according to CDC or manufacturer procedures2

1. Disassemble the system: filters, valve, elastic straps, tube, and any other parts recommended by manufacturer

2. Clean and sanitize in warm water with mild detergent at manufacturer’s recommended temperature; NEVER use organic solvent

3. Drain water from respirator and allow it to air-dry in a clean and sanitary location

4. Follow manufacturer’s guide for other cleaning and sanitizing procedures

Source: Image courtesy of McKinsey design team. McKinsey & Company 39

McKinsey & Company



40

High-level specifications: Powered air-purifying respirator

Source: Image courtesy of McKinsey design team.

1. https://www.cdc.gov/coronavirus/2019-ncov/hcp/infection-control-recommendations.html, https://www.ncbi.nlm.nih.gov/books/NBK294223/2. Derived from interviews with supply-chain experts

Head-top unit

Battery-powered blower

A battery-powered motor driving fan(s) to pull air through the HEPA required by manufacturers

A tube carrying filtered air to head-top unit

A head top designed in variety of ways for needs in workplaces such as medical, hazardous, corrosive, or nuclear3

Functionality Key technical specifications

Tube

Typ. Value1,2

Style: Helmet, tight fitting, or loose fitting Depends on need

US OSHA Assigned Protection Factor 25–1000

Weight 0.4–1.5 kg

Operating temperature -10 – 54 ˚C

Certification (eye and face protection) ANSI Z87.1

Raw material HDPE or rubber

Length 66–96 in

Weight 0.1–0.3 kg

Assembly adjustability Yes/No

Certification NIOSH Approval

Airflow (liter per minute) 170–230

Weight 0.9–1.5 kg

Run time 4–12 hours

Operational temperature -5 – 54 ˚C

Ingress protection (IP rating) IP 53–67

3

2

1

Not exhaustive

1

2

3

McKinsey & Company



41

PAPR: Manufacturing process overviewPAPR is a system solution consisting of subcomponents: facepiece, tube, belt, filter, and blower


Not to scale

Overall production process

Manual assembly by trained operators1

Automated testing and calibration cycle times up to 1 min/system

PAPR system certification requires the system to be tested (eg, exact match of tube, facepiece, and blower)

Circuit and circuit-board components

Metals, such as copper, steel, aluminum

Filter media


Assembled system flow rate, noise, filtration media, and filter lifespan are key performance criteria for full system

Certification of system design by manufacturer is generally maintained for 10–15 years

Manufacturers are audited at random by NIOSH


Tube HEPA Belt Facepiece

Testing needed for raw material input, particularly facepiece or hood input due to blood splattering test for medical use

Blower Submodule manual assembly

Production line requires fixturing and validation

Mold tooling for subassembly a bottleneck to ramp-up: 2–3 months to create and approve tooling

Engineering plastics: polyethylene (eg, Tyvek), polycarbonate, ABS, PVC

EPDM rubber or alternatives (eg, neoprene, silicone)

Battery raw material (eg, lithium-ion polymer)

System testing and calibration PAPRComponent name

Source: Derived from interviews with supply-chain experts; image courtes of McKinsey design team

1. Include glue, screws, tape, or other required materials to enable production

Inventory Production process Likely low nonmed capacity available

Likely some nonmed capacity available

Likely sufficient capacity available Details follow

Illustrative

McKinsey & Company



42

Blower (PAPR subcomponent): Manufacturing process overviewA subcomponent of PAPR system that appears to face a substantial supply constraint

Battery Airtight container

Electronics control unit

DC motor-fan module

Submodule manual assembly

Finished product testing

Manual assembly by trained operators1

Automated testing and calibration cycle times up to 1 min/system

Less-efficient DC motor-fan module can be considered despite shorter operational hours

Expanding airtight-container production requires additional tooling sets (lead time >1 month); interim solution can consider production through CNC machining

Additional shifts can expand the production line (mostly manual assembly)

The DC motor-fan and battery design should be efficient (>4hr operational hours at <1.5kg size) and effective (>170 liter air/min)

The container should have stringent engineering tolerance and be tested to prevent >30-nm particle leak

Source: Derived from interviews with supply chain experts; https://engineering.berkeley.edu/news/2020/04/readily-deployable-respirators-could-help-frontline-healthcare-workers/


1. Include glue, screws, tape, or other required materials to enable production

Production process



Can we relax some testing requirements (eg, shorter battery life or louder operational noise) to help expand production without affecting user protection?

PAPR system certification requires system to be tested (eg, exact match of tube, facepiece, and blower)

BlowerComponent name

Not to scale Inventory Production process Likely low nonmed

capacity available Likely some nonmed capacity available

Likely sufficient capacity available

Illustrative

Documents

COVID-19 airway protection PPE overview/media/McKinsey/About Us/COVID...specific products or organizations are solely for illustration and do not constitute any endorsement or recommendation